A 250-310 GHz Power Amplifier With 15-dB Peak Gain in 130-nm SiGe BiCMOS Process for Terahertz Wireless System

• Published in: IEEE transactions on terahertz science and technology Vol. 12; no. 1; pp. 1 - 12
• Main Authors: Li, Xingcun, Chen, Wenhua, Zhou, Peigen, Wang, Yunfan, Huang, Fei, Li, Shuyang, Chen, Jixin, Feng, Zhenghe
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 01.01.2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Balun; Baluns; Bandwidth; Bandwidths; Broadband; Broadband amplifiers; broadband power amplifier (PA); CMOS; Conductors; gain-boosting; Impedance; Power amplifiers; power combiner; Power combiners; Power gain; Power generation; SiGe; Silicon germanides; stagger-tuned; three-conductor; THz PA; Transmission lines; Wireless communication
• ISSN: 2156-342X; 2156-3446
• DOI: 10.1109/TTHZ.2021.3099057

This article presents a broadband THz power amplifier (PA) operating close to the maximum oscillation frequency ( f max ) with proposed power combining and stagger-tuned gain boosting techniques. A compact broadband power combiner based on the compensated three-conductor transmission line (T-line) balun is proposed to simultaneously achieve broadband matching and power combining. A 4-stage stagger-tuned gain boosting amplifier operating closely to f max is investigated to achieve a flattened power gain. Based on the proposed techniques, a broadband 300-GHz PA is implemented in a 130-nm SiGe BiCMOS process with f t / f max = 350/450 GHz. It exhibits a peak gain of 15 dB and 3-dB bandwidth of 67 GHz (247-314 GHz) with 2.5 V supply voltage. At 290 GHz, a 5-dBm maximum output power P OUT-MAX was measured with a 1-dB compressed output power OP −1 dB of 3.3 dBm and a maximum PAE of 1.19%. The measured output power P OUT-MAX and OP -1dB of the PA are 2.2-5 dBm and 0.6-3.3 dBm over 250-300 GHz, respectively. To the best of our knowledge, this PA achieves the highest operational frequency and widest bandwidth compared with other works in SiGe/CMOS process operating closely to f max .